Ten Russian diplomats were unable to attend this week's United Nations General Assembly in New York having been refused visas.
The official, since named by Russian media, had reportedly been supplying intelligence to the U.S. for decades.
Russian foreign minister Sergey Lavrov said American pressure on the Iran nuclear deal is designed to create a pretense for conflict.
Foreign Minister Sergey Lavrov said a military conflict between Washington and Tehran would be an "international crisis."
Foreign Ministry spokesperson Maria Zakharova said the efforts of the western Allies "should of course not be exaggerated."
"Considering that we have met over the past two weeks for two times, that's a reason for some optimism," Russian Foreign Minister Sergey Lavrov told Secretary of State Mike Pompeo.
"Our American colleagues strongly oppose even mentioning the Paris Climate Agreement in the strategy, as well as the United Nations' 2030 sustainable development goals," Russian Foreign Minister Sergey Lavrov said.
"The launch aimed to confirm the advanced missile system's capabilities and flight characteristics," the Russian Defense Ministry said.
"We will not obey such sanctions," Turkish President Recep Tayyip Erdogan said, adding that his government saw Washington's move as "violating the global balance."
Russia's foreign minister gave his thoughts on the odds of an armed clash and said Russian meddling claims show Washington does not "respect the American choice at all."
Russian Foreign Minister Sergey Lavrov said the idea a troll farm could blemish U.S. elections "makes a mockery" of American politics.
Sergey Lavrov says U.S. criticism won't prevent the two leaders from reconvening.
Moscow's top diplomat traveled with the Russian delegation to Finland, and Trump's performance has delighted the Kremlin greatly.
The two leaders began the day with a tête-à-tête—and are now in a bigger meeting with officials.
Top diplomats from China, the EU, France, Germany, Iran, Russia and the U.K. believe the nuclear deal "is in the security interest of all."
Kim Jong Un complimented Russia but scowled for the cameras in a historic summit with Moscow's top diplomats. On Russian television, his expression mysteriously changed.
"We will do everything so that our Christian, orthodox values are fortified against these sorts of threats."
Russia's Sergei Lavrov has accepted the invitation of North Korea's foreign minister.
In a long interview with state media, Lavrov seemed to reiterate comments made by Kremlin aide Yury Ushakov, who said Trump invited Putin to Washington.
Since 2001, the U.S. has been involved in several ongoing overseas conflicts with no clear end in sight.
President Trump could decide whether to attack Syria as soon as "later today," a move that could draw a Russian military response.
Russia's top diplomat argued that U.S. military presence in Syria was illegal and rebutted accusations over the poisoning of an ex-Soviet spy.
At least 20 countries expelled 139 suspected Russian spies in solidarity with the United Kingdom.